They are painted white to help cool down the containers, but everybody calls them the Black Ships, just like everybody knows their flags are meaningless. The money for the retrofitted container ships is American and European, and the reason they anchor near the coast of every war and disaster is that they will take passengers for free, but not to America or Europe.
Nobody knows where they take them. But they know what lies behind them, and when the containers are nearly full they push their children aboard however they can, and remain on the rafts watching them leave.